Drill-tube section.



P. BOYD & A. M. SAUNDERS.

DRILL TUBE SECTION.

1,287,203. a I Patented Dec. 10, 1918.

g 31 L a I r r INVENTOR BY @71 M44 UNITED STATES PATENT OFFICE. f

] ?ETER BOYD, OE BEAVER, AND AUGUSTE'S M. SAUNDERS, OF McKE-ESPORT, PENNSYL-. I VANIA, ASSIGNORS TO NATIONAL TUBE COMPANY, OF PITTSBURGH, PENNSYL- VANIA, A CORPORATION OF NEW JERSEY.

DRILL-TUBE SECTION.

Application filed March 26, 1918. Serial No. 224,856.

T all whom it may concern:

Be it known that we, Pn'rnn Born,'of Beaver, in the county of Beaver, and AU- GUSTUS M. SAUNDERS, of McKeesport, in the county of Allegheny, both in the State of Pennsylvania, have invented certain new and useful Improvements in Drill-Tube Sections, of which the following is a specification.

a separate device referred to as the tool joint and usually of the box and pin type.

Other styles of joint are in use, but this is the commonest form. According to our in vention the drill tube is made up of tubular sections which are in onepiece from end to end and have their opposite ends shaped to form a box and pin connection, the ends of the section being upset and shaped in a manner defined more particularly hereinafter so as to facilitate the drilling operation by giving the driller fewer joints to contend with and by avoiding certain other disadvantages arising in the old types.

The accompanying drawings illustrate an embodiment of the invention illustrated.

Figure 1 is an elevation of a drill tube made up of our improved sections;

Figs. 2 and 3 are vertical sections respec-, tively of the lower end of one section and l the upper end of the adjoining section.

. and outward, by several operations worked out by practice so as to increase the outside diameter -and to decrease the inside diameter, the inside diameter being graduat the lower end. The outside diameter 'is increased sufficiently and then swaged and drawn to leave room for the cut-ting of the Specification of Letters Patent. Patented D915, 10, 1918,

tapered thread or pinv D and to leave a shoulder E for engagement by the end of the box so as to limit theamount of turning movement of one on the other in fastening them together and thus prevent stripping or injury to the threads and also the cracking of one or the other which sometimes occurs because of torsional strains and the rough handling to which they aresubj ected. Thetapered face F on the inside of the upset pin end is approximately parallel to the taper of the thread D. The totaldistance of the upset portion, from the shoulder G to the end is made longer than is necessary for the screw joint initially out. By reason of the surplus length from the end back to the shpuld'er G the tubes may be ret-hreaded a number of times when they become worn without weakening the joint. The constant screwing of the sections to. gether. as they are lowered into the well and unscrewing'them as they are raised wears the threads, and they are also sometimes injured in handling so that the possibility of numerous rethreadings is asubstantial advantage. For example, if the threads D become worn or otherwise injured the pin end may be rethreaded as indicated in dotted lines at H, cutting back the lower end J v of the pin to the point K and carrying stantially identical with the original joint.

'Referring'to the box and shown in Fig. 3, the end is upset to provide similar features of advantage) The external shoulder M, provides a convenient means for attaching a liftingor holding tool when the tube is being withdrawn and the sections 1mscrewed from one another. The metal is thickened inwardly so that when the initial tapered box thread N is worn or otherwise injured a new thread 0 or other threads, as wear takes place, can be cut and the initial end P of th box may be carried back to the point Q, leaving a box which is substantially identical with that initially formed.

With a section ofi this sort having its opposite ends upset and shaped as in Figs.

2 and 3 respectively, the work of the driller is immensely simplified. The joints can be rethreaded a number of times without weakening them and they are originally of the simplest and strongest construction as Well as providing a cheaper drill tube on the end than heretofore used, as there is only one joint in the coupling instead of three, and no welds resorted to to obtain heavy ends. What We claim is 7 An improved drill tube section comprising a hollow metal tube having its ends integrally shaped and threaded to form a tapered threaded box and pin joint the ends being upset outward to form shoulders for engagement by the lifting or other tools,

onthe threads in screwing the sections together, the ends also being upset inward and for a length greater than is required for the joint when new so that new threads may be formed when the initial threads wear out and may be extended further into the upset portions and the outer ends of said upset portions removed, thus providing a new joint practically identical with the initial one. n

In witness whereof, we have hereunto signed our names.

PETER BOYD. AUGUSTUS M. SAUNDERS. 

